We prove several results in the theory of topological cardinal invariants involving the game-theoretic versions of the weak Lindel & ouml;f degree and of cellularity. One of them is related to Bell, Ginsburg and Woods's 1978 question of whether every weakly Lindelof regular first-countable space has cardinality at most continuum and another one is connected with Arhangel'skii's 1970 question on the weak Lindel & ouml;f degree of the G delta topology on a compact space. We provide a few application of our results, including some bounds on the cardinality of sequential and radial spaces. We finish with a series of counterexamples, which show the sharpness of our results and disprove a few natural conjectures about the impact of infinite games on topological cardinal invariants.

Cardinal inequalities involving the weak Rothberger and cellularity games

Bella, Angelo;Spadaro, Santi
2025-01-01

Abstract

We prove several results in the theory of topological cardinal invariants involving the game-theoretic versions of the weak Lindel & ouml;f degree and of cellularity. One of them is related to Bell, Ginsburg and Woods's 1978 question of whether every weakly Lindelof regular first-countable space has cardinality at most continuum and another one is connected with Arhangel'skii's 1970 question on the weak Lindel & ouml;f degree of the G delta topology on a compact space. We provide a few application of our results, including some bounds on the cardinality of sequential and radial spaces. We finish with a series of counterexamples, which show the sharpness of our results and disprove a few natural conjectures about the impact of infinite games on topological cardinal invariants.
2025
Cardinal inequality
Infinite games
Elementary submodel
Cardinal inequality
Infinite games
G delta topology
Elementary submodel
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11769/643356
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